Animal communication

Between August 2005 and December 2006, 139 boat surveys were conducted in
Sepetiba Bay, Brazil to sample behavioral patterns and environmental parameters during
the occurrence of marine tucuxi groups and aggregations. Aggregations were defined as
several groups gathered in an area totaling more than 100 animals, usually engaged in a
specific behavior. A total of 65 aggregations (x=177) and 192 groups (x=18) were
recorded. Marine tucuxi groups and aggregations differed regarding behavioral activity,
geographical location and age composition. Aggregations were temporal associations of
several marine tucuxi groups performing foraging/feeding activities probably in response
to prey species, abundance, and distribution. Aggregations were primarily located at the
interior of the Bay where local topography may aid dolphins in pursuing and herding
schools of prey. Presence of neonates and calves was highly correlated with aggregations,
reflecting the potential importance aggregations have in the protection, developmental
and learning processes of younger animals.

The signature whistles of related Atlantic spotted dolphins ( Stenella frontalis) in the Bahamas were evaluated for similarity. Judges compared the contour patterns of signature whistles pair-wise between 19 dolphins. Whistle parameters between the signature whistles of individuals were statistically compared. There were no significant differences between the signature whistles of male and female calves when the similarity of their whistles was compared to their mothers. However, there was a tendency with female calves more likely to produce signature whistles similar to their mothers' whistles. Three out of five female calves produced signature whistles that were "very similar" or "similar" to the signature whistles of their mothers. Two out of four male calves produced signature whistles that were "similar" to the signature whistles of their mothers. The signature whistles of mother and calf pairs were more likely to be "similar" to each other than the signature whistles of sibling pairs.

Previous qualitative assessment indicated that signature whistles of temporarily captured, free-ranging dolphins remain stable over periods of 2--12 years. This study reports on the stability of signature whistle parameters in wild female Atlantic spotted dolphins in the Bahamas over five or more years and between changes in age class. Signature whistles from seven female dolphins were pooled into blocks of 'early' and 'late' years for the time assessment. Signature whistles from five females were pooled by age class for the second analysis. Duration, minimum frequency, maximum frequency, and change in frequency were measured from spectrograms of whistles for statistical analysis. No significant changes were found in any of the signature whistle parameters either between early and late periods of time or with a change in age class.

This thesis challenges dualistic human and animal ontologies by interpreting science fiction (sf) literature, and argues that whereas words can equivocate and obscure meaning, bodies do not lie. Linguistics and semiology extend the definition of "language" to include human and nonhuman gestures and movement, and posthumanist theory expands definitions of "human" and "animal" to explore species boundaries. Scrutinizing opposing dualisms ultimately questions Western epistemology and authority, allowing for an exploration of embodied animal communications within the larger discourse on species and speciesism. This perspective results in a more comprehensive understanding of the interdependence of all species: human, animal, and "other." Although the fictional texts I employ use fantastic elements to posit hypothetical realities, current scientific research reveals that communication with nonhuman animals is indeed possible.

The Sargassum community consists of a unique and idverse assemblage of fauna critical to pelagic food chains. Associated organisms presumably have adaptations to assist in finding Sargassum. This study investigated cues used for habitat location and selection by the Sargassum crab, Portunus sayi. Chemical detection trials were conducted with a two-chamber choice apparatus with Sargassum spp. and Thalassia testudinum as source odors. Visual detection trials (devoid of chemical cues) and habitat selection trials were conducted in which crabs were given a choice of habitats. Results showed that P. sayi respoded to chemical odors from Sargassum spp. Crabs visually located habitats but did not visually distinguish between different habitats. In habitat selection trials, crabs selected Sargassum spp. over artificial Sargassum and T. testudinum. These results suggest that crabs isolated from Sargassum likely use chemoreception from longer distances ; within visual proximity of a potential patch, crabs use both chemical and visual information.

Evidence for conceptual semantics is well established in monkeys, however this basis of human language is less evident in the great apes. In order to study semantic communications in chimpanzees, I analyzed alarm calls produced towards a blimp as it was flying overhead. I then replayed a set of these alarm calls to the chimps on a different day. The chimps appeared to act in a manner consistent with the presence of the blimp. The calls they produced in response to the playback stimuli were nearly identical to the calls that were produced during the actual flyover. Though the data collected were not sufficient to support a definitive claim, it does appear that the chimpanzees of the study have a meaning-laden vocalization for the aerial stimuli. Whether this call is specific to the blimp or generalizable to other aerial threats is yet to be determined.